Is there any way I can inspect these items above?
Iam guessing the vavle cap / crank case is gona have to be remove to inspect the motor.

Also during the compression test, I removed all the spark plugs prior to testing the FIRST cylinder or do I just remove the spark plug to the cylinder I'm testing and leave the 3 remaining in UNTIL THEY'RE TESTED?

THANKS in advance guys-

I will be donating 5-10$ when I can figure out what the heck is causing me this less than SATISFIED number readings, to help keep this great site going; because having a 2nd and 3rd opinion really helps when trying to troubleshoot the problem/issue.

Have A Great Day All! Thanks Again! =]

SPONSORED LINKS

Do you

have the same problem?

Yes

No

Sunday, April 19th, 2009 AT 6:01 PM

2 Replies

RASMATAZ

MEMBER

What could lead reading, because I was kind of expecting low 200's on all cylinders.

Xx Excessive carbons will raise the engine compression

Also during the compression test, I removed all the spark plugs prior to testing the FIRST cylinder or do I just remove the spark plug to the cylinder I'm testing and leave the 3 remaining in UNTIL THEY'RE TESTED?

Xx Remove all the plugs and block wide open the throttle plate.

IS IT THE RINGS OR THE VALVES?

If compression is low in one or more cylinders, you can isolate the problem to the valves or rings by squirting a little 30 weight motor oil into the cylinder through the spark plug hole and repeating the compression test. The oil temporarily seals the rings.

If the compression readings are higher the second time around, it means the rings and/or cylinder is worn. No change in the compression readings would tell you the cylinder has a bad valve.

A leakdown or cylinder leakage test is similar to a compression test in that it tells you how well your engine's cylinders are sealing. But instead of measuring pressure, it measures pressure loss.

A leak down test requires the removal of all the spark plugs. The crankshaft is then turned so that each piston is at top dead center (both valves closed) when each cylinder is tested. Most people start with cylinder number one and follow the engine's firing order.

A threaded coupling attached to a leakage gauge is screwed into a spark plug hole. Compressed air (80 to 90 psi) is then fed into the cylinder.

An engine is great condition should generally show only 5 to 10% leakage. An engine that's still in pretty good condition may show up to 20% leakage. But more than 30% leakage indicates trouble.

The neat thing about a leakage test (as opposed to a compression test) is that it's faster and easier to figure out where the pressure is going. If you hear air coming out of the tailpipe, it indicates a leaky exhaust valve. Air coming out of the throttle body or carburetor would point to a leaky intake valve. Air coming out of the breather vent or PCV valve fitting would tell you the rings and/or cylinders are worn.

A leakage test can also be used in conjunction with a compression test to diagnose other kinds of problems.

A cylinder that has poor compression but minimal leakage usually has a valvetrain problem such as a worn cam lobe, broken valve spring, collapsed lifter, bent push rod, etc.

If all the cylinders have low compression but show minimal leakage, the most likely cause is incorrect valve timing. The timing belt or chain may be off a notch or two.

If compression is good and leakage is minimal, but a cylinder is misfiring or shows up weak in a power balance test, it indicates a fuel delivery (bad injector) or ignition problem (fouled spark plug or bad plug wire

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Sunday, April 19th, 2009 AT 6:31 PM

JIMMYL645I

MEMBER

Thanks for the great info, they're very detailed and alot better than what i've been hearing from some of the local shops around here. They seem to be only giving me half ass-ed answers, and wants my money.

I will look deepier into the whole situation and will probably try a leak down test this week, after I try squirting 5w-30 into the cylinders before testing the compression to see if it actually gives me a higher number.

I will be more than happy to donate 10$ after I narrow down the problem, as this will save me some time and money during repair. I feel, I should include the helper in my SAVINGS (money/time) by sharing a portion with you =]

if theres any other info you have, that I should check or look at please let me know. I will try everything you suggest or refer me to. ( Your definately more thorough than myself and most people i've talk to )

and 1 last thing, could you please tell me what I need to perform a leak down test.

Required tools, how much time, and if I need another person assisting me in the leakdown.

Thanks you so much for showing intrest in helping me with this problem i've been more than concern with for the past 2-3 months.